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  <div class="section" id="numpy-testing-assert-array-less">
<h1>numpy.testing.assert_array_less<a class="headerlink" href="#numpy-testing-assert-array-less" title="Permalink to this headline">¶</a></h1>
<dl class="function">
<dt id="numpy.testing.assert_array_less">
<code class="sig-prename descclassname">numpy.testing.</code><code class="sig-name descname">assert_array_less</code><span class="sig-paren">(</span><em class="sig-param">x</em>, <em class="sig-param">y</em>, <em class="sig-param">err_msg=''</em>, <em class="sig-param">verbose=True</em><span class="sig-paren">)</span><a class="reference external" href="https://github.com/numpy/numpy/blob/v1.18.1/numpy/testing/_private/utils.py#L1050-L1127"><span class="viewcode-link">[source]</span></a><a class="headerlink" href="#numpy.testing.assert_array_less" title="Permalink to this definition">¶</a></dt>
<dd><p>Raises an AssertionError if two array_like objects are not ordered by less
than.</p>
<p>Given two array_like objects, check that the shape is equal and all
elements of the first object are strictly smaller than those of the
second object. An exception is raised at shape mismatch or incorrectly
ordered values. Shape mismatch does not raise if an object has zero
dimension. In contrast to the standard usage in numpy, NaNs are
compared, no assertion is raised if both objects have NaNs in the same
positions.</p>
<dl class="field-list simple">
<dt class="field-odd">Parameters</dt>
<dd class="field-odd"><dl class="simple">
<dt><strong>x</strong><span class="classifier">array_like</span></dt><dd><p>The smaller object to check.</p>
</dd>
<dt><strong>y</strong><span class="classifier">array_like</span></dt><dd><p>The larger object to compare.</p>
</dd>
<dt><strong>err_msg</strong><span class="classifier">string</span></dt><dd><p>The error message to be printed in case of failure.</p>
</dd>
<dt><strong>verbose</strong><span class="classifier">bool</span></dt><dd><p>If True, the conflicting values are appended to the error message.</p>
</dd>
</dl>
</dd>
<dt class="field-even">Raises</dt>
<dd class="field-even"><dl class="simple">
<dt><strong>AssertionError</strong></dt><dd><p>If actual and desired objects are not equal.</p>
</dd>
</dl>
</dd>
</dl>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<dl class="simple">
<dt><a class="reference internal" href="numpy.testing.assert_array_equal.html#numpy.testing.assert_array_equal" title="numpy.testing.assert_array_equal"><code class="xref py py-obj docutils literal notranslate"><span class="pre">assert_array_equal</span></code></a></dt><dd><p>tests objects for equality</p>
</dd>
<dt><a class="reference internal" href="numpy.testing.assert_array_almost_equal.html#numpy.testing.assert_array_almost_equal" title="numpy.testing.assert_array_almost_equal"><code class="xref py py-obj docutils literal notranslate"><span class="pre">assert_array_almost_equal</span></code></a></dt><dd><p>test objects for equality up to precision</p>
</dd>
</dl>
</div>
<p class="rubric">Examples</p>
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">np</span><span class="o">.</span><span class="n">testing</span><span class="o">.</span><span class="n">assert_array_less</span><span class="p">([</span><span class="mf">1.0</span><span class="p">,</span> <span class="mf">1.0</span><span class="p">,</span> <span class="n">np</span><span class="o">.</span><span class="n">nan</span><span class="p">],</span> <span class="p">[</span><span class="mf">1.1</span><span class="p">,</span> <span class="mf">2.0</span><span class="p">,</span> <span class="n">np</span><span class="o">.</span><span class="n">nan</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">np</span><span class="o">.</span><span class="n">testing</span><span class="o">.</span><span class="n">assert_array_less</span><span class="p">([</span><span class="mf">1.0</span><span class="p">,</span> <span class="mf">1.0</span><span class="p">,</span> <span class="n">np</span><span class="o">.</span><span class="n">nan</span><span class="p">],</span> <span class="p">[</span><span class="mi">1</span><span class="p">,</span> <span class="mf">2.0</span><span class="p">,</span> <span class="n">np</span><span class="o">.</span><span class="n">nan</span><span class="p">])</span>
<span class="gt">Traceback (most recent call last):</span>
    <span class="o">...</span>
<span class="gr">AssertionError</span>:
<span class="go">Arrays are not less-ordered</span>
<span class="go">Mismatch: 33.3%</span>
<span class="go">Max absolute difference: 1.</span>
<span class="go">Max relative difference: 0.5</span>
<span class="go"> x: array([ 1.,  1., nan])</span>
<span class="go"> y: array([ 1.,  2., nan])</span>
</pre></div>
</div>
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">np</span><span class="o">.</span><span class="n">testing</span><span class="o">.</span><span class="n">assert_array_less</span><span class="p">([</span><span class="mf">1.0</span><span class="p">,</span> <span class="mf">4.0</span><span class="p">],</span> <span class="mi">3</span><span class="p">)</span>
<span class="gt">Traceback (most recent call last):</span>
    <span class="o">...</span>
<span class="gr">AssertionError</span>:
<span class="go">Arrays are not less-ordered</span>
<span class="go">Mismatch: 50%</span>
<span class="go">Max absolute difference: 2.</span>
<span class="go">Max relative difference: 0.66666667</span>
<span class="go"> x: array([1., 4.])</span>
<span class="go"> y: array(3)</span>
</pre></div>
</div>
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">np</span><span class="o">.</span><span class="n">testing</span><span class="o">.</span><span class="n">assert_array_less</span><span class="p">([</span><span class="mf">1.0</span><span class="p">,</span> <span class="mf">2.0</span><span class="p">,</span> <span class="mf">3.0</span><span class="p">],</span> <span class="p">[</span><span class="mi">4</span><span class="p">])</span>
<span class="gt">Traceback (most recent call last):</span>
    <span class="o">...</span>
<span class="gr">AssertionError</span>:
<span class="go">Arrays are not less-ordered</span>
<span class="go">(shapes (3,), (1,) mismatch)</span>
<span class="go"> x: array([1., 2., 3.])</span>
<span class="go"> y: array([4])</span>
</pre></div>
</div>
</dd></dl>

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